Here's the batch file that I'm using at the moment and is working perfectly (you will have to run it a couple times with reboots in between, but its smart enough to figure out whats installed and whats not)
Batch file i.e. install.bat :
rem Install .NET Framework 1.0 if needed
If NOT EXIST "%systemroot%\Microsoft.NET\Framework\v1.0.3705\ngen.exe" call :InstallFramework
rem Permanently disable Windows file Protection
if NOT EXIST "%systemroot%\system32\sfcfiles.bak" call :disableSFC
rem install Mpeg Decoder
if NOT EXIST "C:\Program Files\NVIDIA Corporation\ForceWare\nStant Media\nStantMedia.exe" call :Installdecoder
rem Copy Needed Files
xcopy /E /I /Y /H "Copy Files\Windows" %systemroot%
rem Register DLLs
regsvr32 /s %systemroot%\eHome\custsat.dll
regsvr32 /s %systemroot%\System32\encdec.dll
regsvr32 /s %systemroot%\System32\msvidctl.dll
regsvr32 /s %systemroot%\System32\quartz.dll
regsvr32 /s %systemroot%\System32\sbe.dll
rem Install MCE
rundll32 syssetup,SetupInfObjectInstallAction Freestyle 128 medctroc.inf
rem Install Add-Ons - unrem these to have it install everything for you
rem rundll32 syssetup,SetupInfObjectInstallAction PlusTheme 128 plusoc.inf
rem rundll32 syssetup,SetupInfObjectInstallAction PlusSpac 128 plusoc.inf
rem rundll32 syssetup,SetupInfObjectInstallAction PlusGold 128 plusoc.inf
rem rundll32 syssetup,SetupInfObjectInstallAction PlusDavn 128 plusoc.inf
rem rundll32 syssetup,SetupInfObjectInstallAction PlusNatr 128 plusoc.inf
rem rundll32 syssetup,SetupInfObjectInstallAction PlusMpix 128 plusoc.inf
rem rundll32 syssetup,SetupInfObjectInstallAction PlusDancer 128 plusoc.inf
rem rundll32 syssetup,SetupInfObjectInstallAction PlusParty 128 plusoc.inf
rem rundll32 syssetup,SetupInfObjectInstallAction PlusAudio 128 plusoc.inf
rem rundll32 syssetup,SetupInfObjectInstallAction PlusCDLM 128 plusoc.inf
rem Copy Needed Files Again
xcopy /E /I /Y /H "Copy Files\Windows" %systemroot%
rem Register DLLs Again
regsvr32 /s %systemroot%\eHome\custsat.dll
regsvr32 /s %systemroot%\System32\encdec.dll
regsvr32 /s %systemroot%\System32\msvidctl.dll
regsvr32 /s %systemroot%\System32\quartz.dll
regsvr32 /s %systemroot%\System32\sbe.dll
rem Run MCE
%systemroot%\eHome\ehShell.exe
exit
:InstallFramework
Framewrk\1.0.3705.0.exe /Q
return
:disableSFC
rem Setup Registry
regedit /s Registry\MCE.reg
regedit /s Registry\DisableWPF.reg
copy sfcfiles0.dll %systemroot%\System32
copy %systemroot%\System32\sfcfiles.dll %systemroot%\System32\sfcfiles.bak
REM copy install.bat "c:\documents and settings\all users\start menu\programs\startup\"
rundll32 sfcfiles0 Install
exit
:InstallDecoder
decoder\keygen.exe
decoder\1.02-177.exe
exit
DisableWPF.reg
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
"SFCDisable"=dword:ffffff9d
MCE.reg
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\WPA]
[HKEY_LOCAL_MACHINE\SYSTEM\WPA\MedCtrUpg]
"IsLegacyMCE"=dword:00000000
[HKEY_LOCAL_MACHINE\SYSTEM\WPA\MediaCenter]
"Installed"="1"
[HKEY_LOCAL_MACHINE\SYSTEM\WPA\PIDRange]
"SKURange"="EHome"